README

   1 NAME
   2     HTTP::Daemon - a simple http server class
   3
   4 SYNOPSIS
   5       use HTTP::Daemon;
   6       use HTTP::Status;
   7
   8       my $d = HTTP::Daemon->new || die;
   9       print "Please contact me at: <URL:", $d->url, ">\n";
  10       while (my $c = $d->accept) {
  11           while (my $r = $c->get_request) {
  12               if ($r->method eq 'GET' and $r->uri->path eq "/xyzzy") {
  13                   # remember, this is *not* recommended practice :-)
  14                   $c->send_file_response("/etc/passwd");
  15               }
  16               else {
  17                   $c->send_error(RC_FORBIDDEN)
  18               }
  19           }
  20           $c->close;
  21           undef($c);
  22       }
  23
  24 DESCRIPTION
  25     Instances of the `HTTP::Daemon' class are HTTP/1.1 servers that listen
  26     on a socket for incoming requests. The `HTTP::Daemon' is a subclass of
  27     `IO::Socket::INET', so you can perform socket operations directly on it
  28     too.
  29
  30     The accept() method will return when a connection from a client is
  31     available. The returned value will be an `HTTP::Daemon::ClientConn'
  32     object which is another `IO::Socket::INET' subclass. Calling the
  33     get_request() method on this object will read data from the client and
  34     return an `HTTP::Request' object. The ClientConn object also provide
  35     methods to send back various responses.
  36
  37     This HTTP daemon does not fork(2) for you. Your application, i.e. the
  38     user of the `HTTP::Daemon' is responsible for forking if that is
  39     desirable. Also note that the user is responsible for generating
  40     responses that conform to the HTTP/1.1 protocol.
  41
  42     The following methods of `HTTP::Daemon' are new (or enhanced) relative
  43     to the `IO::Socket::INET' base class:
  44
  45     $d = HTTP::Daemon->new
  46     $d = HTTP::Daemon->new( %opts )
  47         The constructor method takes the same arguments as the
  48         `IO::Socket::INET' constructor, but unlike its base class it can
  49         also be called without any arguments. The daemon will then set up a
  50         listen queue of 5 connections and allocate some random port number.
  51
  52         A server that wants to bind to some specific address on the standard
  53         HTTP port will be constructed like this:
  54
  55           $d = HTTP::Daemon->new(
  56                    LocalAddr => 'www.thisplace.com',
  57                    LocalPort => 80,
  58                );
  59
  60         See IO::Socket::INET for a description of other arguments that can
  61         be used configure the daemon during construction.
  62
  63     $c = $d->accept
  64     $c = $d->accept( $pkg )
  65     ($c, $peer_addr) = $d->accept
  66         This method works the same the one provided by the base class, but
  67         it returns an `HTTP::Daemon::ClientConn' reference by default. If a
  68         package name is provided as argument, then the returned object will
  69         be blessed into the given class. It is probably a good idea to make
  70         that class a subclass of `HTTP::Daemon::ClientConn'.
  71
  72         The accept method will return `undef' if timeouts have been enabled
  73         and no connection is made within the given time. The timeout()
  74         method is described in IO::Socket.
  75
  76         In list context both the client object and the peer address will be
  77         returned; see the description of the accept method IO::Socket for
  78         details.
  79
  80     $d->url
  81         Returns a URL string that can be used to access the server root.
  82
  83     $d->product_tokens
  84         Returns the name that this server will use to identify itself. This
  85         is the string that is sent with the `Server' response header. The
  86         main reason to have this method is that subclasses can override it
  87         if they want to use another product name.
  88
  89         The default is the string "libwww-perl-daemon/#.##" where "#.##" is
  90         replaced with the version number of this module.
  91
  92     The `HTTP::Daemon::ClientConn' is a `IO::Socket::INET' subclass.
  93     Instances of this class are returned by the accept() method of
  94     `HTTP::Daemon'. The following methods are provided:
  95
  96     $c->get_request
  97     $c->get_request( $headers_only )
  98         This method reads data from the client and turns it into an
  99         `HTTP::Request' object which is returned. It returns `undef' if
 100         reading fails. If it fails, then the `HTTP::Daemon::ClientConn'
 101         object ($c) should be discarded, and you should not try call this
 102         method again on it. The $c->reason method might give you some
 103         information about why $c->get_request failed.
 104
 105         The get_request() method will normally not return until the whole
 106         request has been received from the client. This might not be what
 107         you want if the request is an upload of a large file (and with
 108         chunked transfer encoding HTTP can even support infinite request
 109         messages - uploading live audio for instance). If you pass a TRUE
 110         value as the $headers_only argument, then get_request() will return
 111         immediately after parsing the request headers and you are
 112         responsible for reading the rest of the request content. If you are
 113         going to call $c->get_request again on the same connection you
 114         better read the correct number of bytes.
 115
 116     $c->read_buffer
 117     $c->read_buffer( $new_value )
 118         Bytes read by $c->get_request, but not used are placed in the *read
 119         buffer*. The next time $c->get_request is called it will consume the
 120         bytes in this buffer before reading more data from the network
 121         connection itself. The read buffer is invalid after $c->get_request
 122         has failed.
 123
 124         If you handle the reading of the request content yourself you need
 125         to empty this buffer before you read more and you need to place
 126         unconsumed bytes here. You also need this buffer if you implement
 127         services like *101 Switching Protocols*.
 128
 129         This method always returns the old buffer content and can optionally
 130         replace the buffer content if you pass it an argument.
 131
 132     $c->reason
 133         When $c->get_request returns `undef' you can obtain a short string
 134         describing why it happened by calling $c->reason.
 135
 136     $c->proto_ge( $proto )
 137         Return TRUE if the client announced a protocol with version number
 138         greater or equal to the given argument. The $proto argument can be a
 139         string like "HTTP/1.1" or just "1.1".
 140
 141     $c->antique_client
 142         Return TRUE if the client speaks the HTTP/0.9 protocol. No status
 143         code and no headers should be returned to such a client. This should
 144         be the same as !$c->proto_ge("HTTP/1.0").
 145
 146     $c->head_request
 147         Return TRUE if the last request was a `HEAD' request. No content
 148         body must be generated for these requests.
 149
 150     $c->force_last_request
 151         Make sure that $c->get_request will not try to read more requests
 152         off this connection. If you generate a response that is not self
 153         delimiting, then you should signal this fact by calling this method.
 154
 155         This attribute is turned on automatically if the client announces
 156         protocol HTTP/1.0 or worse and does not include a "Connection:
 157         Keep-Alive" header. It is also turned on automatically when HTTP/1.1
 158         or better clients send the "Connection: close" request header.
 159
 160     $c->send_status_line
 161     $c->send_status_line( $code )
 162     $c->send_status_line( $code, $mess )
 163     $c->send_status_line( $code, $mess, $proto )
 164         Send the status line back to the client. If $code is omitted 200 is
 165         assumed. If $mess is omitted, then a message corresponding to $code
 166         is inserted. If $proto is missing the content of the
 167         $HTTP::Daemon::PROTO variable is used.
 168
 169     $c->send_crlf
 170         Send the CRLF sequence to the client.
 171
 172     $c->send_basic_header
 173     $c->send_basic_header( $code )
 174     $c->send_basic_header( $code, $mess )
 175     $c->send_basic_header( $code, $mess, $proto )
 176         Send the status line and the "Date:" and "Server:" headers back to
 177         the client. This header is assumed to be continued and does not end
 178         with an empty CRLF line.
 179
 180         See the description of send_status_line() for the description of the
 181         accepted arguments.
 182
 183     $c->send_header( $field, $value )
 184     $c->send_header( $field1, $value1, $field2, $value2, ... )
 185         Send one or more header lines.
 186
 187     $c->send_response( $res )
 188         Write a `HTTP::Response' object to the client as a response. We try
 189         hard to make sure that the response is self delimiting so that the
 190         connection can stay persistent for further request/response
 191         exchanges.
 192
 193         The content attribute of the `HTTP::Response' object can be a normal
 194         string or a subroutine reference. If it is a subroutine, then
 195         whatever this callback routine returns is written back to the client
 196         as the response content. The routine will be called until it return
 197         an undefined or empty value. If the client is HTTP/1.1 aware then we
 198         will use chunked transfer encoding for the response.
 199
 200     $c->send_redirect( $loc )
 201     $c->send_redirect( $loc, $code )
 202     $c->send_redirect( $loc, $code, $entity_body )
 203         Send a redirect response back to the client. The location ($loc) can
 204         be an absolute or relative URL. The $code must be one the redirect
 205         status codes, and defaults to "301 Moved Permanently"
 206
 207     $c->send_error
 208     $c->send_error( $code )
 209     $c->send_error( $code, $error_message )
 210         Send an error response back to the client. If the $code is missing a
 211         "Bad Request" error is reported. The $error_message is a string that
 212         is incorporated in the body of the HTML entity body.
 213
 214     $c->send_file_response( $filename )
 215         Send back a response with the specified $filename as content. If the
 216         file is a directory we try to generate an HTML index of it.
 217
 218     $c->send_file( $filename )
 219     $c->send_file( $fd )
 220         Copy the file to the client. The file can be a string (which will be
 221         interpreted as a filename) or a reference to an `IO::Handle' or
 222         glob.
 223
 224     $c->daemon
 225         Return a reference to the corresponding `HTTP::Daemon' object.
 226
 227 SEE ALSO
 228     RFC 2616
 229
 230     IO::Socket::INET, IO::Socket
 231
 232 COPYRIGHT
 233     Copyright 1996-2003, Gisle Aas
 234
 235     This library is free software; you can redistribute it and/or modify it
 236     under the same terms as Perl itself.
 237